Yarn package



July 27, 1943. ADDING 2,325,127

YARN PACKAGE Filed Dec. 21, 1940 2 Sheets-Sheet l IN V ENTOR.

ATTORNEY July 27, 1943. E. K. GLADDING 2,325,127

YARN PACKAGE Filed Dec. 21, 1940 2 Sheets-Sheet 2 Ernest K.filaddizzg m m Patented July 21, 1943 UNITED STATES PATENT OFFICE- YARN PACKAGE Ernest Knight Gladding, Wilmington, Del., assignor to E. L du Pont de Nemours a Company,

Wilmington, Del., a corporation-of Delaware Application December 21, 1940, Serial No. 371,107

11 Claims. (Cl. 242-159) This invention relates to yarn packages, and is particularly concerned with the production oi. packages comprising synthetic linear polyamide multifilament yarn to which has been applied a sizing composition.

Since the invention is particularly concerned with packages of synthetic linear polyamide multifilament yarn which has been treated with a sizing composition and wound into package form while wet with size, it will, for purposes of i1- lustration, be described specifically with respect to this type of yarn.

This application is a copending application with my application Serial No. 371,106, now Patent No. 2,304,564, for Yarn packages and method and apparatus for producing same, filed of even date herewith, and all the disclosure of my said copending application is intended to be included, by reference, in the present application to the extent that such disclosure is pertinent to the discussion of the present invention.

It is desirable to subject synthetic linear polyamide multifilament yarn to a sizing operation in order to adapt the yarn to various textile operations. The term sizing" refers to the application of an adhesive coating to a yarn to protect the filaments thereof during the subsequent handling of the yarn.

It is important, in preparing packages of sized yarn, to apply the sizing composition to the yarn uniformly. Uniform sizing of synthetic linear polyamide yarn may be eflected, in accordance with a copending application of Edgar W. Spanagel, Serial No. 369,951, filed December 13, 1940, now Patent No. 2,278,902, dated April '7, 1942, by contacting the yarn in its passage from the supply bobbin to the wind-up bobbin with an aqueous solution containing a suitable size, the sized yarn being wound on to the wind-up bobbin while still wet with the sizing composition.

It is well-known in the textile arts to wind yarn packages by a precision winding operation in which the traverse guide or button which is operated by the traverse mechanism, is kept at all times in direct contact with the body of yarn being wound, in order to insure uniform lay-down of the yarn by virtue of the fact that the yarn is always laid down at the position occupied by the thread guide. This precision winding tends to eliminate the well-known phenomena of overthrown ends or loops. In unwinding a package of yarn in which loops are present and particularly where the unwinding is accomplished by unwinding the yarn over one end of the package only (the unwinding generally being accomplished at a high rate of speed), the loops tend to catch in the main body or the yarn package causing yarn and filament breakage and uneven draw-oi! tension. This is especially true when dealing with low denier yarn or when dealing with yarn which has been sized and wound wet according to the bobbin-to-bobbin process described in the copending Spanagel application referred to above.

However, if precision winding is used in the winding of yarn while wet with size which has been applied in accordance with the aforementioned Spanagel process, the yarn windings adhere tenaciously to each other because of the tact that the adhesive size hardens on the bobbin and cements adjacent yarn windings together, and this causes great difliculty in the unwinding of the bobbin in subsequent operations. Precision winding 01' yarn sized and wound while wet is also accompanied by the formation of tuck-unders," i. e., the displacement of yarn windings and the tucking of such windings under adjacent windings. Tuck-unders occur frequently in the wet winding of sized yarn during precision winding, because of occasional shifting of yarn windings on the wind-up bobbin due to the solidifying of the size during drying, and this is especially true in the case of synthetic linear polyamide yarns which swell and shrink successively during the sizing and wet winding and drying and in which the filaments, being round in cross-section tend to roll more readily on each other and thus become displaced, particularly in the presence or the wet size which acts as a lubricant. Tuck-unders also occur in wet-wound sized yarn because of wicking of the size towards the ends of the wind-up bobbin, and are also encountered in yarn which possessed a high twist prior to sizing and which was sized, after twisting, according to the Spanagel procedure, especially when the yarn is subsequently subjected to a high temperature-high humidity operation for setting the twist in the yarn.

The phenomena of loops and tuck-t tders cause particular trouble where the preci ion wound yarn is wound with straight ends as distinguished from beveled ends.

Additionally, where yarn is sized in a bobbinto-bobbin sizing operation and is precision wound while wet, the size tends to collect on the thread guide and, upon drying, becomes a hard abrasive substance which, because of its direct contact with the yarn on the wind-up bobbin, tends to cause filament and yarn breakage.

It is an object of the present invention to pro vide a novel package of yarn, and particularly yarn of the synthetic linear polyamide type, which has been sized and wound while wet with a sizing composition, yet which can be readily unwound under constant tension and with a minimum of breaks.

Other objects of the invention will appear hereinafter.

The objects of the invention are accomplished in general by sizing yarn, particularly yarn of the synthetic linear polyamide type, with a sizing composition comprising an adhesive size embodied in a vaporizable liquid such as water.

winding the yarn while wet, drying the yarn, at least in part. on the wind-up bobbin, and so winding the yarn that at least one and preferably both end sections of the wound-up package conform to the limits set forth below.

The invention can best be understood by reference to the drawings which illustrate one form of yarn package embodying the principles of the present invention. Fig. 1 of the drawings represents a sectional view of the yarn package after the yarn has been completely wound on the bobbin, the bobbin being cut through on its vertical central plane. Fig. 2 of the drawings represents an enlarged sectional view of one end of the yarn package shown in Fig. 1.

In accordance with this invention it has been found that the ease with which yarn sized and wound wet (especlally'when this is accomplished in accordance with the procedure described in the aforementioned Spanagel application, wherein the size after it is applied to the yarn retains at least 50% of its water content for a period of at least one minute after the size application) will unwind in subsequent textile operations such as coning, depends to a large extent on the taper at the end of the package. Thus sized yarn which is wound wet into a package having two straight ends can not be unwound satisfactorily and this is especially true where the unwinding is accomplished over one end of the package where that end is wound straight.

It is essential that the taper on that end of a wound package from which the yarn is unwound, which package is composed of yarn which has been sized and wound wet, falls within certain limits: in the case of a package unwound by an end-over operation, that end over which the yarn is unwound must fall within the said limits, and where the yarn is unwound from end to end. then both ends must fall within the said limits. One form of taper is illustrated in the yarn package shown in the drawings. In the drawings curves AE and GF represent lines formed by the intersection of the tapered ends of the-bobbin with the vertical central plane of cross-section. H represents the point furthest removed from the bobbin AG. E and F (the practical ends of the taper) represent the first points along the curves AH and GF which fall within a distan e of 0.15 inch measured perpendicularly from a line drawn through H parallel to AG. It has-been found that when the angles X formed between AG and AE and between AG and 01'' are less than 65 and when no segments of the curves AE and FG (for example, segments AU, W or YZ as shown in Fig. 2 of the drawings) have tangents forming angles of 90 or greater with any plane parallel with AG and when the sum of the segments of said curves (1. e., AU+VW+YZ as shown in 8. 2) having tangents forming angles in excess of 65' with any plane parallel with AG does not exceed 0.15 inch then yarn packages formed from sized yarn which is wet when wound unwind with ease. and substantially no underwindings (tuck-unders) are formed during the winding of the sized yarn package.

one form of yarn package conforming to the principles of this invention and illustrated in the fi ure of the drawings, can be produced by utilizing the procedure and apparatus forming the basis of my aforementioned copending application for Yarn packages and method and apparatus for producing same.

Although the subject matter of my copending application has been included herein by reference, it is desired to described briefly the operation of the process and apparatus of my said copending application. Yarn wound up in accordance with my said copending application is unwound from a supply package, is passed through a wash-board tension guide. thence through a pair of leaf guides disposed perpendicularly to the position of the wash-board tension guides.being then passed into contact with a roller which dips into an aqueous sizing composition and which applies the sizing composition by contact with the yarn. The yarn then passes through a thread guide and thence in contact with a thread guide arm mounted on any conventional form of traverse bar, said guide arm being out of contact with the wind-up package onto which the yarn is wound. The guide arm mounted on the traverse bar is so designed as to remain in contact with the yarn during the wind-up while being mounted to move at random so as to impart to the yarn, during wind-up. a random lay down especially at the ends of the yarn package. One form of guide arm arrangement adapted to effect this result comprises a yam-contacting arm pivotally mounted at the end of the traverse bar and provided with means which limits the extent of movement of the guide arm in both directions so that the total angle of movement of the guide arm around its pivot is in the neighborhood of 40". Obviously there is nothing critical about the angle of movement of the guide arm, and other types of random motion guides may be used in place of that especially described above, all of which is pointed out in my copending application. Heating means are preferably provided in proximity to the wind-up bobbin in order to dry the size composition on the yarn according to any desired rate.

Yarn sized and wound up by the use of the random motion guide and apparatus especially described above and illustrated in Figs. 1 to 5 of the drawings of my copending application results in the yarn package as shown in the figure of the drawings of the present application.

It will be understood that although the procedure and apparatus described in my copending application and further described above, is preferred for the winding of a bevel end package such as is illustrated in the drawings of this application, nevertheless any other form of traverse motion in which the traverse guide is out of contact with the wind-up yarn package and which will produce a yarn package having the limitative characteristics set forth above can be used to produce yarn packages coming within the scope of this invention. Thus a yarn traverse motion in which the traverse is of diminishing scope and is so operated (for-example, by the design in contour of cams controlling the traverse motion) as to produce yarn packages within the definition set forth above, may be used. Also, another form of traverse motion that may be used is one in which the traverse stroke is of constant length but has its position or origin shifted according to a predetermined plan for the purpose of building up bevel end packages coming within the scope of the present invention. It is within the skill of those familiar with the design and operation of yarn traverse mechanisms, in the line of the information contained herein, to design alternative forms of traverse motion which will accomplish the results embodied in this invention.

It will be understood that the invention is concerned with packages having a substantial thickness of yarn cake, i. e., 0.20 inch and above, between the surface of the yarn supporting bobbin and the outside of the yarn package.

The yarn package illustrated in the drawings is free of tuck-overs and is built up with tapered ends free from loops" as that term is used in the conventional sense and can be unwound, even when the yarn is drawn off from one end of the yarn package wholly, in a rapid orderly manner and under substantially constant and even very low tension, as in a. coning operation, with substantial freedom from yarn or filament breakage.

Although the invention has been described with particular reference to synthetic linear polyamide yarns, having specifically in mind polyhexamethylene adipamide yarns, the invention may also be utilized in the production of packages of sized yarns composed of materials other than synthetic linear polyamides. For example, other synthetic linear polymer yarns may be sized and wound in accordance with the present invention. Synthetic linear polymer yarns forming the preferred species of the present invention, are described in United States Letters Patent 2,071,250, 2,130,253 and 2,130,948. Other types of yarns such as cotton, wool, silk, viscose rayon and cellulose derivative (e. g. cellulose acetate) rayon may be utilized in the practice of this invention.

Since the above description is largely illustrative rather than limitative, any modification or variation thereof which conforms to the principles of the invention are intended to be included within the scope of the claims.

I claim:

1. A Wound package of textile yarn from which the yarn can be removed by drawing the same from one end thereof comprising a yarn support and yarn windings at least some of which adhere to each other through the medium of a dry adhesive size, characterized in that a line drawn in any axial plane of the package between points representing the approximate limits of an end of the package, form, with the yarn supporting surface, an angle which substantially embraces the end of the yarn package and which is not in excess of 65, being further characterized in that no portion of the said package end has tangents forming angles of 90 or greater with the axis of the package, the sum of those portions at said end of the package, which have tangent angles between 65 and 90, not exceeding 0.15 inch.

2. The yarn package of claim 1 in which the said end of the package has a sinuous outside contour.

3. A wound package of synthetic linear polymer textile yarn from which the yarn can be removed by drawing the same from one end thereof comprising a yarn support and yarn windings at least some of which adhere to each other through the medium of a dry adhesive size, characterized in that a line drawn in any axial plane of the package between points representing the approximate limits of an end of the package, form, with the yarn supporting surface, an angle which substantially embraces the end of the yarn package and which is not in excess of 65.

4. A wound package of synthetic linear polymer textile yarn from which a yarn can be removed by drawing the same from one end thereof comprising a yarn support and yarn windings at least some of which adhere to each other through the medium of a dry adhesive size, characterized in that a line drawn in any axial plane of the package between points representing the approximate limits of an end of the package, form, with the yarn supporting surface, an angle which substantially embraces the end 'of the yarn package and which is not in excess of 65, being further characterized in that no portion of the said package end has tangents forming angles of or greater with the axis of the package.

5. A wound package of synthetic linear polymer textile yarn from which a yarn can be removed by drawing the same from one end thereof comprising a yarn support and yarn windings at least some of which adhere to each other through the medium of a dry adhesive size, characterized in that a line drawn in any axial plane of the package between points representing the approximate limits of an end of the package, form, with the yarn supporting surface, an angle which substantially embraces the end of the.

yarn package and which is not in excess of 65, being further characterized in that no portion of the said package end has tangents forming angles of 90 or greater with the axisof the package, the sum of those portions at said end of the package, which have tangent angles between 65 and 90", not exceeding 0.15 inch.

6. A wound package of synthetic linear polyamide textile yarn from which a yarn can be removed by drawing the same from one end thereof comprising a yarn support and yarn windings at least some of which adhere to each other through the medium of a dry adhesive size, characterized in that a line drawn in any axial plane of the package between points representing the approximate limits of an end of the package, form, with the yarn supporting surface, an angle which substantially embraces the end of the yarn package and which is not in excess of 65.

7. A wound package of synthetic linear polyamide textile yarn from which a yarn can be removed by drawing the same from one end thereof comprising a yarn support and yarn windings at least some of which adhere to each other through the medium of a dry adhesive size, characterized in that a line drawn in any axial plane of the package between points representing the approximate limits of an end of the package, form, with the yarn supporting surface, an angle which substantially embraces the end of the yarn package and which is not in excess of 65, being further characterized in that no portion of the said package end has tangents forming angles of 90 or greater with the axis of the package.

8. A wound package of synthetic linear polyamide textile yarn from which a yarn can be removed by drawing the same from one end thereof comprising a yarn support and yarn windings at least some of which adhere to each other through the medium of a dry adhesive size, characterized in that a line drawn in any axial plane 01' the package between points representing the approximate limits of an end of the package, form, with the yarn supporting surface, an angle which substantially embraces the end of the yarn package and which is not in excess of 65, being further characterized in that no portion of the said package end has tangents forming angles of 90 or greater with the axis of the package, the sum oi those portions at said end of the package, which have tangent anglesbetween 65 and 90, not exceeding 0.15 inch.

9. A wound package of poiyhexamethylene adipamide textile yarn from which a yarn can be removed by drawing the same from one end thereof comprising a yarn support and yarn windings at least some of which adhereto each other through the medium oi a dry adhesive size, characterized in that a line drawn in any axial plane 01' the package between points representing the approximate limits of an end oi the package, form, .with theyam supporting surface, an angle which substantially embraces the end of the yarn package and which is not in excess 10. A wound package of, polyhexamethylene adipamide textile yarn from which a yarn can be removed by drawing the same from one end thereof comprising a yarn support and yarn windings at least some of which adhere to each other through the medium of a. dry adhesive size. characterized in that a line drawn in any axial plane 01 the package between points representing the approximate limits of an end or the package. term, with the yarn supporting surface, an angle which substantially embraces the end of the yarn package and which is not in excess of being further characterized in that no portion of the said package end has tangents forming angles of or greater with the axis of the packa e.

11. A wound package 01' polyhexamethylene adipamide textile yarn from which a yarn can be removed by drawing the same from one end thereof comprising a yarn support and yarn windin s at least some or which adhere to each other through the medium of a dry adhesive size. characterized in that a line drawn in any axial plane of the package between points representing the approximate limits of an end oi the package, form, with the yarn supporting surface, an angle which substantially embraces the end 01' the yarn package and which is not in excess of 65", being further characterized in that no portion of the said package end has tangents forming angles of 90 or greater with the axis or the package, the sum of those portions at said end of the package, which have tangent angles between 65 and 90, not exceeding 0.15 inch.

ERNEST KNIGHT GLADDING. 

